There is a large body of literature on the interface of childhood temperament characteristics and psychiatric symptoms. A recent meta-analysis indicates that the temperamental characteristic of emotionality is moderately associated with both internalizing and externalizing disorders. The etiology of these associations, however, are largely unknown. The proposed project will examine the genetic and environmental influences underlying the associations between emotionality and internalizing and externalizing symptoms. Data from the Georgia Twin Registry, a population-based sample of 838 twins age 4 - 18, will be used to address several specific aims. These data wilt allow for behavior genetic analyses of both emotionality and symptomatology as well as analyses of covariation between emotionality and each symptom dimension. Previous studies have not yet elucidated whether the associations between emotionality and internalizing and externalizing disorders are due to common underlying genetic or environmental influences. The proposed study will make a unique contribution to the development psychopathology literature by elucidating the nature of these associations using multivariate behavior genetic model-fitting analyses. [unreadable] [unreadable]